Cops are working with Coastguard and Search and Rescue teams in the village of Paull.
A Humberside Police spokesman said: “A report was received at around 1.45pm this afternoon (Tuesday, 26 February), of what was believed to be body in the water close to the ferry terminal in Hull.
“Our teams are currently working with the Coastguard and Search and Rescue in and around the area.”
Eyewitnesses have reported a huge police presence and divers searching the waters.
One man told the Hull Daily Mail: “There’s something going on here at Paull front – I can see loads of police and divers in the water at the sea front but I’m not sure what’s going on.
“A police van is here, as well as search and rescue in a 4×4 and it looks like whatever it is could be fairly serious.”
Another man said: “When I got here, there was two cars and a van and a couple of boats in the river. They just sailed past.
“Now, there’s just the one police car and two coppers stood on the river bank.”
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